Coated pipe comprising polyolefin layer with enhanced adhesion

Abstract

The present invention relates to a structure comprising (i) a layer or profile (A) composed of a first material, and (ii) a polyolefin layer or profile (B) adjacent to layer or profile (A) which is composed of a composition comprising a base resin comprising a polyolefin, characterized in that the surface of any or both of layer or profile (A) and layer or profile (B) has/have been treated with a composition comprising an organosilicon compound before (A) and (B) are brought adjacent to each other, to a process for the production of such a structure, to an article, in particular a coated pipe, comprising such a structure and to the use of a composition comprising an organosilicon compound as an adhesion promoter in such a structure.

The invention claimed is: 
     
       1. A structure consisting of
 (i) a layer or profile (A) comprising a metal or metal alloy, and 
 (ii) a polyolefin layer or profile (B) adjacent to layer or profile (A) which comprises a composition comprising a base resin comprising a polyolefin, 
 characterized in that the surface of layer or profile (A) has been treated with a composition comprising an organosilicon compound before (A) and (B) are brought adjacent to each other; and 
 wherein the polyolefin of the composition layer or profile (B) comprises from 0.02 to 1.0 mole % of adhesion promoting groups; wherein the structure is a pipe; and wherein the polyolefin of the composition layer or profile (B) is a terpolymer of ethylene, a vinyl silane, and a monomer selected from the group consisting of an anhydride functional monomer and maleic anhydride. 
 
     
     
       2. A structure according to  claim 1  wherein the organosilicon compound comprises one or more hydrolysable groups which after hydrolysis yield silanol groups. 
     
     
       3. A structure according to  claim 2  wherein the organosilicon compound comprises the structural element: 
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , and R 3 , independently are selected from alkyl groups and acetyl groups. 
       
     
     
       4. A structure according to  claim 1  wherein the treatment of the surface of layer or profile (A) comprises applying a solution of the organosilicon compound to the surface. 
     
     
       5. Coated pipe according to  claim 1  wherein layer/profile (A) of the multilayer structure comprises steel and has an outer surface which has been treated with said composition comprising an organosilicon compound before (A) and (B) are brought adjacent to each other. 
     
     
       6. The structure of  claim 1 , wherein the metal alloy is steel. 
     
     
       7. Process for the production of a pipe characterized in that the surface of a layer or profile (A) composed of a metal or metal alloy is treated with a composition comprising an organosilicon compound before (A) and a polyolefin layer or profile (B) comprising a composition comprising a polyolefin are brought adjacent to each other; wherein the structure consists of layer or profile (A) and polyolefin layer or profile (B); and wherein the polyolefin of the composition layer or profile (B) comprises from 0.02 to 1.0 mole % of adhesion promoting groups; and wherein the polyolefin of the composition layer or profile (B) is a terpolymer of ethylene, a vinyl silane, and a monomer selected from the group consisting of an anhydride functional monomer and maleic anhydride. 
     
     
       8. The process of  claim 7 , wherein the metal alloy is steel. 
     
     
       9. A structure consisting of
 a. a layer or profile (A) comprising a metal or metal alloy, and 
 b. a polyolefin layer or profile (B) adjacent to layer or profile (A) which comprises a composition comprising a base resin consisting of a polyolefin, 
 characterized in that the surface of layer or profile (A) has been treated with a composition comprising an organosilicon compound before (A) and (B) are brought adjacent to each other; and 
 wherein the polyolefin of the composition layer or profile (B) comprises from 0.02 to 1.0 mole % of adhesion promoting groups; wherein the structure is a pipe; and wherein the polyolefin of the composition layer or profile (B) is a terpolymer of ethylene, a vinyl silane, and a monomer selected from the group consisting of a C 1 -C 6  alkyl acrylate, a C 1 -C 6  methyacrylate, a hydroxyl functional monomer, an anhydride functional monomer, an acrylic acid, a methacrylic acid, and vinyl acetate. 
 
     
     
       10. The pipe of  claim 9 , wherein the monomer is maleic anhydride. 
     
     
       11. The pipe of  claim 9 , wherein the metal alloy is steel.